HDU 2035 人见人爱A^B

#include <iostream>
#include <cstdio>
using namespace std;

int quickPow(long long a,long long b,int k){
int ret=1;
while (b)
{
if(b&1){
ret=ret*a%k;
}
a=a*a%k;
b>>=1;
}
return ret%k;
}
int main(){
int a,b;
while (scanf("%d%d",&a,&b)==2)
{
if(!a&&!b)break;
printf("%d\n",quickPow(a,b,1000));
}
return 0;
}